The present invention provides an improved system for efficiently controlling the floppy disk drive unit. In particular, the system minimizes power consumption when the floppy disk drive unit halts its read-and-write operations.
All conventional floppy disk drive units are provided with mechanical units such as a disk driver and head positioner. The disk driver causes the disk to rotate at a constant speed by means of the spindle motor. The drive circuit constantly receives power even when it remains inoperative. The head positioner is provided with a pulse motor, for example, which causes the read-write head to shift itself it a specific track position, while the excited coil also constantly receives power so that the head position does not deviate after the head has been moved. Thus, since the floppy disk drive unit still employs conventional means of supplying power, a substantial amount of power is constantly supplied to the excited coil of the pulse motor even when the floppy disk drive unit remains inoperative and executes no read-and-write operations. As a result, power dissipation is a problem. Although conventional floppy disk drive units stop the spindle motor and the read-write circuit to save power and protect the head from wear while no read-and-write operations are performed, the drive unit still feeds power to the pulse motor to stabilize the position of the head.